Upper Extremity Muscle Innervations

Question 1

Trapezius

Answer 1

Spinal Accessory

C3/4

Question 2

SCM

Answer 2

Spinal accessory

C3/4

Question 3

Rhomboids

Answer 3

Dorsal scapula

C4/5

Question 4

Supraspinatus

Answer 4

Suprascapular
Upper trunk
C5/6

Question 5

Infraspinatus

Answer 5

Suprascapular (after traveling thru spinoglenoid notch)
Upper trunk
C5/6

Question 6

Biceps brachii

Answer 6

Musculocutaneous
Lateral cord
Upper trunk
C5/6

Question 7

Brachialis

Answer 7

Musculocutaneous
Lateral cord
Upper trunk
C5/6

Question 8

Deltoid

Answer 8

Axillary
Posterior cord
Upper trunk
C5/6

Question 9

Teres minor

Answer 9

Axillary
Posterior cord
Upper trunk
C5/6

Question 10

Brachioradialis

Answer 10

Radial n
Posterior cord
Upper trunk
C5/6

Question 11

Serratus anterior

Answer 11

Long thoracic n

C5, 6, 7

Question 12

Pectoralis major

Answer 12

Medial and lateral pectoral n
Medial and lateral cords
Upper, middle, and lower trunks
C5-T1

Question 13

Pronator teres

Answer 13

Median n
Lateral cord
Upper and middle trunk
C6/7

Question 14

Flexor carpi radialis

Answer 14

Median n
Lateral cord
Upper and middle trunk
C6/7

Question 15

Extensor carpi radialis longus

Answer 15

Radial n
Posterior cord
Upper and middle trunks
C6/7

Question 16

Triceps

Answer 16

Radial n
Posterior cord
Upper, middle, and lower trunks
C6, 7, 8

Question 17

Anconeus

Answer 17

Radial n
Posterior cord
Upper, middle and lateral trunks
C6, 7, 8

Question 18

Latissimus dorsi

Answer 18

Thoracodorsal n
Posterior cord
Upper, middle, and lower trunks
C6, 7, 8

Question 19

Extensor carpi ulnaris

Answer 19

Posterior Interosseous Nerve branch
Radial n
Posterior cord
Middle and lower trunks
C7/8

Question 20

Extensor indicis proprius

Answer 20

PIN
Radial n
Posterior cord
Middle and lower trunks
C7/8

Question 21

Extensor digitorum

Answer 21

PIN
Radial n
Posterior cord
Middle and lower trunks
C7/8

Question 22

Flexor digitorum superficialis

Answer 22

Median n
Medial and lateral cords
Middle and lower trunks
C7/8

Question 23

Pronator quadratus

Answer 23

Anterior interosseous n
Median n
Medial and lateral cords
Middle and lower trunks
C7/8 and T1

Question 24

Flexor pollicus longus

Answer 24

AIN
Median 
Medial and lateral cords
Middle and lower trunks
C7/8 and T1

Question 25

FDP 2,3

Answer 25

``` AIN Median n Medial cord Middle and lower trunks C7/8 and T1 ```

Question 26

FDP 4,5

Answer 26

Ulnar n Medial cord Middle and lower trunk C7/8 and T1

Question 27

Abductor pollicus brevis

Answer 27

Median n Medial cord Lower trunk C8/T1

Question 28

Flexor pollicus brevis

Answer 28

Median and ulnar n Medial cord Lower trunk C8/T1

Question 29

Lumbricals 1,2

Answer 29

Median n Medial cord Lower trunk C8/T1

Question 30

Opponens pollicus

Answer 30

Median n Medial cord Lower trunk C8/T1

Question 31

Flexor carpi ulnaris

Answer 31

Ulnar n Medial cord Lower trunk C8/T1

Question 32

Abductor digiti minimi

Answer 32

Ulnar Medial cord Lower trunk C8/T1

Question 33

First dorsal interossei

Answer 33

Ulnar n Medial cord Lower trunk C8/T1

Question 34

Lumbricals 3, 4

Answer 34

Ulnar Medial cord Lower trunk C8/T1

Question 35

Interossei (3 PADs, 4 DABs)

Answer 35

Ulnar Medial cord Lower trunk C8/T1

Question 36

Sensory innervation for lateral forearm

Answer 36

``` Lateral antebrachial cutaneous (LAC) Musculocutaneous Lateral cord Upper trunk C5/6 ```

Question 37

Sensory innervation of medial forearm

Answer 37

``` Medial antebrachial cutaneous (MAC) Ulnar Medial cord Lower trunk C8/T1 ```